42 INTERRELATIONS OF PLANTS AND ANIMALS 



more noticeable. Moths are its chief night visitors. The long 

 proboscis is thrust into the flower and quickly withdrawn, but 

 usually a little pollen is carried off on the palps (projections on the 

 sides of the head). This may be left on the next flower visited. 



Try to determine what other insects, if any, visit the evening 

 primrose at night. 



Draw a single flower split open lengthwise to show the position 

 of the parts, and especially any adaptations to insect pollination. 

 Look for any special means for the prevention of self-pollination. 

 Label all the parts. 



Moth Mullein (Verbascum blattaria). — The moth mullein is 

 one of the most beautiful weeds, despite the fact that few blos- 

 soms are found at any given time. The plant flourishes on dry, 

 waste land, roadsides, and open fields. It was introduced into 

 this country and has since become common here and in Canada. 



The flowers are found in a long, loose raceme. A raceme is 

 like a spike, except that each flower has its own flower stalk devel- 

 oped. Has this cluster yellow or white flowers? Into how many 

 parts is the calyx divided ? The corolla ? Is the corolla perfectly 

 regular? Notice the five stamens. Is there anything peculiar 

 about the filaments ? Are they all of the same length ? In spite 

 of the fact that the flower is called moth mullein, it is not polli- 

 nated to any extent by moths. Bees and flies are the chief pollen 

 bearers. Bees which alight on this flower do so for the purpose 

 of collecting pollen. This they usually gather from the short 

 stamens, while they cling to the longer ones. As the bee lights on 

 another flower, the pollen on the under side of the body is trans- 

 ferred to the stigma of this flower. 



Draw the flower from above, twice natural size. 



Jewelweed (Impatiens biflora). — One of the most prevalent 

 of all our brookside flowers is the jewelweed. It well deserves its 

 name, a pendant flaming jewel of orange. 



This flower is very irregular in shape. Are the flowers single 

 or in clusters? The sepals as well as the petals are colored. The 

 former are three in number, one of which is sacklike in shape and 

 contracted at one end into a spur. The petals are also three in 

 number. Open the flower. Notice how short the filaments of 



